In this edition of the Long Term Ecological Research Network series, editors John Hobbie and George Kling and 58 co-authors synthesize the findings from the NSF-funded Arctic LTER project based at Toolik Lake, Alaska, a site that has been active since the mid-1970s. The book presents research on the core issues of climate-change science in the treeless arctic region of Alaska. As a whole, it examines both terrestrial and freshwater-aquatic ecosystems, and their three typical habitats: tundra, streams, and lakes. The book provides a history of the Toolik Lake LTER site, and discusses its present condition and future outlook. It features contributions from top scientists from many fields, creating a multidisciplinary survey of the Alaskan arctic ecosystem. Chapter topics include glacial history, climatology, land-water interactions, mercury found in the Alaskan arctic, and the response of these habitats to environmental change. The final chapter predicts the consequences that arctic Alaska faces due to global warming and climate change, and discusses the future ecology of the LTER site in the region. Alaskas Changing Arctic is the definitive scientific survey of the past, present, and future of the ecology of the Alaskan arctic.